unit 3 developmental psychology (copy)

introduction to developmental psychology pdf

  • studies how people grow, change and develop throughout their lives

  • looks at physical, cognitive, social, and emotional changes

chronological development

  • specific order and timing of changes that occur as people age

    • milestones happen at certain ages

    • puberty, cognitive decline

thematic development

  • looks at big patterns over lifespan

    • stability and change, nature and nurture, etc,

methods of studying human development

cross sectional

  • observe or test different groups of people of varying ages at a single point in time

How?

  • select participants from different age groups (eg. children, adolescents, adults, older adults)

  • measure specific variables of interest

  • compare results

eg. compare memory performance of 10, 20, 30, 40 to understand how memory changes with age

advantages

  • quick, cost-effect

    • data = collected at one time point

    • faster, less expensive

  • snapshot of differences

    • help identify patterns and trends across the lifespan

disadvantages

  • cohort effects

    • differences might be due to generational/ cultural factors, not because of age

  • no individual development

    • do not track individual changes over time

longitudinal studies

  • observe/ test same group of people over an extended period

how it works

  • select a group of participants and repeatedly measure the same variables at multiple times points throughout their lives

  • allows fir the examination of changes within individuals over time

eg. follow a group of children from age 3 to age 25, assessing their cognitive development

advantages

  • tracking development over time

    • detailed information about how individuals change overtime

    • identify patterns of development

  • less cohort effects

    • same individuals are studied over time

    • differences are more likely due to age-related changes

disadvantages

  • time-consuming and expensive

    • require long-term commitment of resources and time

    • more expensive and logistically challenging

  • attrition

    • participants might drop out the study over time

    • smaller sample size and potentially biased results

  • historical effects

    • events occurring during the study can influence findings

3 major themes of developmental psychology

nature vs nurture

  • whether genetics (nature) or environment (nurture) has a bigger impact on who we become

nature

  • our genes and biological makeup play the most important role in shaping our traits and behaviours

  • studies of twins

    • similarities in intelligence, personality, behaviors, even when they are raised in different environments

  • emphasises that many of our development are determined by DNA and biological processes

nurture

  • believe that surroundings and experiences are more important

    • upbringing, culture, social interactions

    • education, socioeconomic status, life experiences

  • both nature and nurture work together to shape our development

stability and changes

  • whether our traits and behaviours remain consistent throughout life or change over time

stability

  • many aspects of our personality, intelligence, other traits are established early in life and remain constant

  • genetic factors play a crucial role in setting these traits

    • persist as we age

  • regardless of life experiences

  • personality

eg. child who is naturally shy may remain shy throughout adulthood regardless of life experiences

change

  • undergo significant transformations over their lifetime due to various influences

    • life experiences, environment, personal choices

  • traits are not fixed and can evolve with new experiences and circumstances

  • cognitive abilities, social skills, physical capabilities

e.g. someone who is introverted during childhood may become more outgoing due to positive social experiences and personal growth

continuity vs stages

  • centers on how people change and grow over time

continuity

  • development is a gradual, continuous process

  • changes occur slowly and steadily throughout a person’s life

  • development = smooth progression without clear-cut stages

stages

  • development occurs in distinct phases, each marked by specific, qualitative changes

  • theories like Piaget’s stages of development, Erikson’s psychosocial stages

  • people progress through set stages in a specific order

  • highlights these shifts as clear evidence of different ways of understanding and interacting with the world at various life stages

physical development

prenatal development

physical development

  • starts with the germinal stage

    • from conception to two weeks

    • where zygote attaches to the uterine wall

  • in embryonic stage,

    • from 3-8 week

    • major organs form

    • heart begins beating by the fourth week

    • arms and legs start developing

  • during fetal stage

    • 9 week until birth

    • embryo begins to look distinctively human as organs and systems grow and mature

teratogens

  • substances that may lead to birth defects in am embryo or fetus

    • alcohol, drugs, environmental toxins, certain medications

  • impact depends on several factors

    • length of exposure

    • stage of pregnancy that exposure occurs

    • genetic factors

    • type of teratogen

  • maternal illness, genetic mutations, hormonal, environmental factors also influence

maternal illness: rubella (German measles), sexually transmitted infections

  • cross the placenta and harm developing fetus

Genetic mutations: inherited or spontaneous

  • cause physical and cognitive abnormalities

    • down syndrome: extra copy of chromosome 21

    • sickle sell anemia: caused by a mutation in the hemoglobin gene

hormonal imbalances: in mother

  • affect fetal development

    • excess androgens: lead to masculinization of female fetuses

    • insufficient thyroid hormone: impair brain development

environmental factors: poor nutrition, lack of prenatal care, exposure to toxins

  • negatively impact fetal growth and development

most well known teratogens

  • alcohol

  • can lead to fetal alcohol syndrome (FAS)

    • characterised by a range of physical, cognitive, and behavioural problems

    • growth deficiencies, facial abnormalities, intellectual disabilities

  • severity depends on timing, duration, level of exposure

newborn development

reflexes

  • automatic responses that indicate healthy physical and psychological development

rooting reflex

  • baby turns its head toward a touch on the cheek and opens its mouth

  • helps with breastfeeding

startle reflex/ Moro reflex

  • causes a baby to throw its arms out and then pull them back in when startles

  • demonstrates basic protective response

grasping reflex

  • baby closing its fingers around an object placed in its hand

  • shows early motor development

these reflexes indicate that a newborn’s nervous system is functioning correctly and that they are on track for developmental milestones

social connection

  • newborns have natural preference for sights and sounds that promote social responsiveness

    • crucial for early bonding and communication

  • newborns spends more time looking at face-like images

    • innate attraction to human faces

  • infants gaze longer at objects 8-12 inches away

    • typical distance between a nursing infant’s eyes and their mother’s face

  • ensures that newborns engage in eye contact

  • at birth, you have the highest number of brain cells you will ever process

    • but nervous system is still immature

  • as you grow, neural networks become increasingly complex

infant development

maturation

  • natural growth and development process, guided by genetic and biological factors

    • enables individual to reach full potential

  • in infants, maturation is evident in the rapid development of the brain

    • neural networks become increasingly complex

    • allows enhanced cognitive functions and physical abilities

  • rapid brain development is crucial for motor skills, language acquisition, social interactions

    • importance of a nurturing environment

infantile amnesia

  • inability to recall memories from the earliest years of life

  • occurs because the brain structures responsible for long-term memory (hippocampus) are not yet fully developed in infancy

motor development

  • encompasses the progression of physical skills that enable movement and corrdination

  • divided into two categories

    • fine motor skills

    • gross motor skills

fine motor skills

  • small muscles

  • hands and fingers

  • essential for tasks like grasping objects, holding a spoon, eventually writing

gross motor skills

  • larger muscles in the arms, legs, torso

  • crawling, sitting, standing, walking

4-6 months: rolling over

6-8 months: sitting

8-10 months: crawling

9-12 months: standing

12-15 months: walking

childhood development

maturation

  • involves both nature and nurture interacting to shape development

  • from age 3-6

    • rapid brain growth occurs in the frontal lobes

    • enhancing rational planning and the ability to control attention and behaviour

  • intense period of brain development results in significant cognitive and emotional progress

nature provides genetic blueprint

nurture supports these developments

  • studies with rats have shown that those raised in enriched environments developed significantly more cerebral cortex compared to those in impoverished environment    

    • impact of a stimulating environment on brain development

critical period/ sensitive period

  • crucial window of time when the brain is particularly receptive to certain types of learning and development

    • when the brain is highly sensitive to certain experiences

  • exposure to stimuli such as spoken, written, or signed language is essential

    • without it, a person will never fully master language skills

  • lack of visual experience can result in permanant deficits in normal perception

    • neural circuits responsible for these functions need specific experiences to develop properly

imprinting

  • rapid, instinctive learning process that occurs during a critical period in some animal species

    • birds form a strong attachment to the first moving object they encounter (usually parent)

      • allows them to quickly learn to follow and identify their caregivers, ensuring their survival

  • Konrad Lorenz: imprinting in geese

    • showing that goslings would follow him if he was the first object they saw after hatching

  • if these critical periods pass without necessary stimuli

    • brain’s ability to adapt and learn in those areas in significantly diminished

adverse childhood experiences (ACEs)

  • traumatic events in a child’s life

    • abuse, neglect, household dysfunction

  • can have profound and lasting effects on physical, emotional, cognitive development

  • exposed to ACEs have higher risks for mental health issues, etc.

  • disrupt brain development, lead to problems with learning, behavior, etc.

adolescent development

  • childhood to adulthood

  • 12-18 age

  • significant physical, emotional , psychological changes

    • undergo puberty

    • stronger sense of identity

    • seek greater independence

puberty

  • children transition to adulthood

  • triggered by hormonal changes

  •     begins with the activation of the hypothalamic-pituitary-gonadal (HPG) axis

  • experience significant physical and hormonal changes

  • growth spurt

    • rapid increases in height and weight

    • changes in body composition and proportion

  • development of primary sex characteristics

    • maturation of the reproductive organs

  • secondary sex characteristics

    • growth of body hair

    • breast development in girls

    • deeper voice in boys

  • production of sex hormones

    • testosterone in males

    • estrogen in females

menarche (primary)

  • onset of menstruation

  • key milestone in female puberty

  • timing of puberty can vary widely

    • 8-14 for girls

    • 9-15 for boys

  • influenced by genetics, nutrition, environmental factors

  • can affect adolescents’ physical and emotional development

    • may mature different rates compared to peers

the teenage brain

  • significant changes that impact behavior and decision-making

  • synaptic pruning

    • unused neural connections are eliminated

    • increase brain efficiency

  • prefrontal cortex, responsible for rational planning and impulse control, is still development

    • adolescents’ judgment often lags behind their emotional and hormonal development

  • teenagers may experience heightened impulsivity, emotional storms, engage in risky behaviours

  • underdeveloped prefrontal cortex + intense emotions= critical period for learning and growth

adulthood development

emerging adulthood: 18- mid 20s

  • exploration and self-discovery

early adulthood: 20s-30s

  • building careers and forming intimate relationships

middle adulthood: up to age 65

  • stability and personal growth

late adulthood: years after 65

  • reflection, retirement, maintaining health

middle adulthood

  • gradual physical decline

    • reduced muscle mass

    • decreased bone density

    • slower metabolism

    • deteriorated vision and hearing

Reproductive ability peaks in early adulthood and declines with age

  • menopause: late 40s or early 50s

    • end of menstrual cycles

    • significant drop in estrogen levels

  • gradual decrease in testosterone in men

    • affecting energy and mood

    • declined vision and hearing

  • what individuals experience depends on their personal health and habits

    • diets, exercise, stress management

    • can influence impact of these changes

late adulthood

  • various physical and cogntiive changes

  • decline in sensory abilities

    • diminished vision, hearing, taste, smell

  • decreased stamina, strength

    • daily activities more challenging

  • brain undergoes changes

    • reduction in volume of certain areas

    • slower neural processing

    • decrease in cognitive functions

      • memory, problem-solving

Piaget’s cognitive development theory

Jean Piaget

  • influential developmental psychologist concerned with the cognitive development of children

  • studied children and identified 4 main cognitive stages

schemas

  • categories of knowledge that help us interpret and understand the world

  • used to modify/ add to/ change previously existing schemas

  • ex. a child may have schema about a type of animal

    • id their only experience is with small dogs → might believe that all dogs are small

    • if they encounters a big dog → take in new information and modify the previous schema

assimilation

fitting new information into an existing schema

  • taking in new information into our already existing schemas

  • no change to the person’s current interpretation of reality

accommodation

  • changing existing schemas when we gain new information

  • new schemas may develop as a result of the changes

  • perception of reality is changed

ex. when the child encounters a horse

adjusting or creating a new schema when the old one doesn’t work

  • they might assimilate this information and call the animal a dog at first

  • accommodation allows the child to adapt the existing schema to incorporate the knowledge that some four-legged animals are horses

4 stages of cognitive development

  • sensorimotor stage: birth to 2 years

  • preoperational stage: ages 2-7

  • concrete operational stage: ages 7-11

  • formal operational stage: ages 12 and up

sensorimotor stage (birth to 2 years)

  • use senses and motor skills to learn about the world

  • look and listen to things, touch and move objects

milstone: object permanence

  • learning that things continue to exist even when they cannot be seen

preoperational stage (2-7)

  • learn through pretend play

  • struggle with logic and taking the point of view of other people

  • become proficient in using mentals symbols

  • struggling with understanding the idea of constancy

Lack of conservation

understanding that quantity stays the same despite changes in shape

  • understanding that changing the form of a substance or object does not change its amount, overall volume, or mass

  • ex. child believes that the taller, narrower glass contains more liquid

lack theory of mind

  • ability to infer the mental states of other people

  • = egocentrism

    • difficulty seeing from another’s perspective

animism

  • believe that inanimate objects have feelings and thoughts just like living creatures

concrete operational stage (7-11)

  • much stronger at using logic

  • egocentrism begins to disappear

    • better at thinking about how other people might view a situation

  • tend to struggle with abstract and hypothetical concepts

reversibility

  • actions that can be reversed

  • ex. water can be frozen then thawed to become liquie

  • 2+3=5, 5-3=2

formal operational stage (12+)

  • increase in logic, ability to use deductive reasoning, understanding of abstract ideas

  • become capable of seeing multiple potential solutions to problems

  • think more scientifically about thw world around them

  • not all people achieve formal operational thinking

Vygotsky’s theory of the social child

  • emphasized how the child’s mind grows through interaction with the socio-cultural environment

  • children gain knowledge and skills primarily through interactions with others within their cultural and social environment

  • emphasized learning is not an isolated process

    • but is deeply embedded in the context of social relationships and cultural tools

the zone of proximal development

  • range of tasks that a child can perform with help but not yet independently

Scaffolding:

  • is the temporary support provided to move someone through their ZPD

cognitive development in adults

  • experiences changes in cognitive capabilities as they progress throguh lifespan’’

crystalizated intelligence

  • accumulated knowledge and vocabulary

  • remains relatively stable through adulthodo

fluid intelligence

  • reasoning speed and abstract problem-solving

  • peaks in early adulthood, declines with age